First off, welcome to the site.
It sounds like you have a good head start on some pretty good techniques. The scangauge would give you a good idea on acceleration techniques and the like and you may end up liking it too much to sell it. From what I understand, you could sell it for about what you pay for it. Personally, I have a 1990 vehicle which is not scangauge compatible. I am building the MPGuino, however, and hope to have that operational by this weekend sometime. As far as the battery dying, I don't think it would be enough pull on the battery to worry about killing it too much to start again (usually we're talking a minute or less of down time). Think about when people leave their headlights on all night. It isn't going to kill it in a matter of a minute (which is on the longer side that you'd leave your motor off anyway...at least in my experience, the longest I think it's off is maybe 30-45 seconds tops).
Look forward to your posts elsewhere
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"It is foolish and wrong to mourn the men who died. Rather we should thank God that such men lived."
- General George S. Patton, Jr
